The invention relates to an end connector for contacting at least two shielded cables.
DE-AS 1,043,450 discloses an end connector of the generic type in which cables comprising a plurality of cores i.e., insulated wires, are guided towards a common end connection point by the individual cores of the cables being guided in insulating chambers of an insulating body. In this arrangement, the individual cores of the cables are linked in the insulating chambers of the insulating body to the corresponding other cores of the other cables (for example by twisting). The introduction of the insulated ends of the cores of the cables into the insulating chambers of the insulating body here prevents a short circuit by contacting of the insulated ends of different cores of the cables. A metallic sleeve, which can be filled with casting resin, can in addition be placed over the end connection point.
In this hitherto known end connector disadvantages arise to the effect that screening or shielding of the cables at the end connection point is only possible to a limited extent.
It is an object of the invention to design an end connector for contacting a plurality of shielded cables in such a way that the cables, the connected cores and the shields are insulated from one another at the end connection point and that the end connection point has shielding against external disturbing electromagnetic fields.
This object is achieved according to the invention, in an end connector of the generic type for contacting a plurality of shielded cables, by an arrangement wherein cores of the cables to be connected to one another are insulated from other cores of the cables at a connection point,
wherein the cores of the cables to be connected to one another are conductively connected in a manner known per se to form at least one core strand,
wherein the cables and the core strand(s) are guided towards the end connection point in insulating chambers of an insulating body,
wherein, in the case of a plurality of core strands, the individual core strands are introduced in separate insulating chambers of the insulating body,
wherein the insulating body is closed off with a cap for covering the connection points of the cores of the cables, there simultaneously being an electric insulation between the connection points of the cores of the cables and the cap,
wherein shields of the individual shielded cables are also connected to one another,
wherein the cap is a plastic cap having a metallic outer surface,
wherein the plastic cap has a hole through which the connected shields of the individual cables are inserted and then electrically conductively connected to the metallic outer surface, and
wherein the plastic cap is surrounded with an insulating layer, the application of which simultaneously entails a fixing of the position of the cables.
A further advantage of the end connector according to the invention compared to the known prior art consists in the fact that the introduction of the cables is simplified since the insulating chambers of the insulating body are initially open at one side.
The end connector according to the invention is designed in such a way that the cables to be contacted are initially guided towards the connection point in duct-shaped insulating chambers which are U-shaped, i.e. are open on one side.
During the introduction of the cables into the end connector according to the invention, it is possible to connect the corresponding cores of the individual cables first of all and then to bend the cables and the core strands, obtained by the connection of the corresponding cores, in such a way that, in shape, they correspond to the course of the insulating chambers of the insulating body according to the invention. This course is essentially such that the cables run toward the end connection point from the same direction, the core strands being bent back in the direction from which the cables run towards the connection point, with the result that they can be introduced into insulating chambers of the insulating body. The connected shields of the cables are taken along further in a direction such that they can be threaded or inserted through a hole in the plastic cap of the end connector according to preferred embodiments of the invention.
In this arrangement, a plurality of cables can be guided towards the connection point in a common insulating chamber. It is also contemplated to bend a core strand in such a way that it is introduced into an insulating chamber in which one or more cables are guided towards the connection point. In this arrangement, a short circuit can in general not occur, because both the cable and the individual cores of the cables are each independently surrounded by an insulation. Thus only the contact points of the individual cores of the cables are uninsulated. In an advantageous embodiment, the insulation of the individual cores of the cables with resect to one another is especially ensured by each of the core strands being introduced into its own special insulating chamber.
In order to close off the insulating body according to the invention, a plastic cap can be placed on when the cables and the core strands have been introduced into the insulating chambers of the insulating body. The plastic cap here has a hole through which the connected shields of the individual cables can be threaded. This plastic cap can, for example, be secured on the insulating body by a clamping device or screw thread.
The plastic cap closing off the insulating body is designed in such a way that it closes off the individual insulating chambers in mutually insulated fashion and has a metallic outer surface which shields the connection points. Particularly advantageous shielding of the cables, even in the region of the end connection point, is achieved if the connected shields of the individual cables are electrically conductively connected to the metallic outer surface of the plastic cap. For this purpose, the shields of the individual cables are attached in a manner known per se to the metallic outer surface of the plastic cap - for example by soldering or by the shields being clamped fast - after the shields have been threaded through the hole in the plastic cap. The plastic cap covering the end connection point must here have a size, particularly as regards the metallic outer surface, such that it protrudes clearly beyond the points at which the connection points of the individual cores of the cables in the insulating chambers are situated. It is also contemplated to guide back the shields of the cables in an insulating chamber of the insulating body in such a way that they protrude from the plastic cap. Shielding of the end connection point can be achieved by the shields being bent around the plastic cap and being electrically conductively secured on the metallic outer surface of the plastic cap. Insulation of the metallic outer surface of the plastic cap can be achieved by surrounding the plastic cap with an insulating material. This insulating material can be secured on the plastic cap in a manner known per se. A contemplated embodiment of this insulation of the plastic cap consists in the use of a heat-shrinkable sleeve, which is placed over the end connection point and then heated. In another embodiment of the insulation of the plastic cap, the metallic outer surface of the plastic cap is coated with a hot-melt adhesive. The advantage of using the hot-melt adhesive consists in the fact that not only is it possible to coat the metallic outer surface of the plastic cap in a simple manner but that, furthermore, the insulating chambers accommodating the cables and core strands can be filled with this hot-melt adhesive, improved fixing of the position of the cables thus being achieved as compared with the use of a heat-shrinkable sleeve.
Other objects, advantages and novel features of the present invention will become apparent from the following detailed description of the invention when considered in conjunction with the accompanying drawings.